Metamath Proof Explorer


Theorem fvffz0

Description: The function value of a function from a finite interval of nonnegative integers. (Contributed by AV, 13-Feb-2021)

Ref Expression
Assertion fvffz0 N0I0I<NP:0NVPIV

Proof

Step Hyp Ref Expression
1 simpr N0I0I<NP:0NVP:0NV
2 simp2 N0I0I<NI0
3 simp1 N0I0I<NN0
4 nn0re I0I
5 nn0re N0N
6 ltle INI<NIN
7 4 5 6 syl2anr N0I0I<NIN
8 7 3impia N0I0I<NIN
9 elfz2nn0 I0NI0N0IN
10 2 3 8 9 syl3anbrc N0I0I<NI0N
11 10 adantr N0I0I<NP:0NVI0N
12 1 11 ffvelcdmd N0I0I<NP:0NVPIV